The disclosure relates to a wireless power transmitting technology. More particularly, the embodiment relates to a wireless power transmitter capable of increasing power transmission efficiency by improving a structure of the wireless power transmitter, and a wireless power transmission system.
A wireless power transmission or a wireless energy transfer refers to a technology of wirelessly transferring electric energy to desired devices. In the 1800's, an electric motor or a transformer employing the principle of electromagnetic induction has been extensively used and then a method of transmitting electrical energy by irradiating electromagnetic waves, such as radio waves or lasers, has been suggested. Actually, electrical toothbrushes or electrical razors, which are frequently used in daily life, are charged based on the principle of electromagnetic induction. The electromagnetic induction refers to the generation of an electric current through induction of a voltage when a magnetic field is changed around a conductor. The electromagnetic induction scheme has been successfully commercialized for electronic appliances having small sizes, but represents a problem in that the transmission distance of power is too short.
Besides the electromagnetic induction scheme, the long-distance transmission using the resonance and the short-wavelength radio frequency has been suggested as the wireless energy transfer scheme.
Recently, among wireless power transmitting technologies, an energy transmitting scheme employing resonance has been widely used.
Since an electric signal generated between the wireless power transmitter and the wireless power receiver is wirelessly transferred through coils in a wireless power transmitting system using resonance, a user may easily charge electronic appliances such as a portable device.
However, according to the related art, there is limitation to increase a Quality factor (Q) and power transmission efficiency between a transmitter side and a receiver side.